In Nield’s case, this means literally imagining what the surface of the Earth might look like after hundreds of millions of years’ worth of tectonic transformations have deformed it beyond all recognition. Supercontinent could thus be read alongside Jan Zalasiewiez’s The Earth After Us as a useful guide for thinking about radical landscape change on a truly inhuman timescale.

Nield writes, for example, that, “even if some civilization of 200 million years ago had completely covered [the Earth] in cities and then wiped itself out in some gigantic global nuclear holocaust, nothing—not even the faintest trace of some unnatural radioisotope—would now remain on the surface.” Some of us might think that writing books, for example, is a way to achieve immortality—or winning an Oscar or becoming a national leader—yet covering the entire planet with roads and buildings is still not enough to guarantee a place in any sort of collective future memory. Everything will be erased.

The book goes from a speculative, but apparently realistic, scenario in which subduction zones might open in the Caribbean—thus dragging North America back toward a seemingly inexorable collision with Eurasia—to the future implications of past tectonic activity. Supercontinents have come and gone, Nield reminds us, and the cycle of these mega-islands is “the grandest of all the patterns in nature.” “750 million years before Pangaea formed,” he writes, “yet another [supercontinent] broke up; and before that another, and so on and on, back into the almost indecipherable past.”

At one point, Nield asks, “what of older supercontinents? What of the supercontinent that broke up to give us Pangaea? And the one before that? Compared with Pangaea, those lost worlds seem truly lost. As with all geological evidence, the older it is, the less of it survives, the more mangled it has become and the harder it is to interpret.”

It is all but impossible to picture them—to see oneself standing on them—as you can with Pangaea. They have their magical names, which lend them reality of a sort despite the fact that, for some, even their very existence remains controversial. About Rodinia, Pannotia, Columbia, Atlantica, Nena, Arctica or distant Ur, the mists of time gather ever more thickly.

The amazing thing is that this cycle will continue: long after North America is expected to reunite with Eurasia, which itself will have collided with North Africa, there will be yet another splintering, following more rifts, more bays and inland seas, in ever-more complicated rearrangements of the Earth’s surface, breeding mountain ranges and exotic island chains. And so on and so on, for billions of years. Bizarre new animals will evolve and bacteria will continue to inter-speciate—and humans will long since have disappeared from the world, unable to experience or see any of these future transformations.

While describing some of the potential ecosystems and landscapes that might result from these tectonic shifts, Nield writes that “our knowledge of what is normal behavior for the Earth is extremely limited.”

Indeed, he suggests, the present is not a key to the past: geologists have found “that there were things in the deepest places of Earth history for the unlocking of whose secrets the present no longer provided the key.” These are known as “no-analog” landscapes.

That is, what we’re experiencing right now on Earth potentially bears little or no resemblance to the planet’s deep past or far future. The Earth itself has been, and will be again, unearthly.

In any case, I mention all this because of a quick description found roughly two-fifths of the way through Nield’s book where he discusses lost ecosystems—landscapes that once existed here but that no longer have the conditions to survive.

Those included strange forests that, because of the inclination of the Earth’s axis, grew in almost permanent darkness at the south pole. “These forests of the polar night,” Nield explains, describing an ancient landscape in the present tense, “withstand two seasons: one of feeble light and one of unremitting dark. Today’s world has no equivalent of this eerie ecosystem. Their growth rings show that each summer these trees grow frenetically. Those nearer the coast are lashed by megamonsoon rains roaring in from [the lost continent] of Tethys, the thick cloud further weakening the feeble sunshine raking the latitudes at the bottom of the world.”

There is something so incredibly haunting in this image, of thick forests growing at the bottom of the world in a state of “unremitting” darkness, often lit only by the frozen light of stars, swaying now and again with hurricane-force winds that have blown in from an island-continent that, today, no longer exists.

Whatever “novel climates” and unimaginable geographies lie ahead for the Earth, it will be a shame not to see them.